major reference

...substances are used in so many different ways by so many different people for so many different purposes that no one view or one definition could possibly embrace all the medical, psychiatric, psychological, sociological, cultural, economic, religious, ethical, and legal considerations that have an important bearing on addiction. Prejudice and ignorance have led to the labelling of all use...

forms of chemical dependency

the body’s physical and/or psychological addiction to a psychoactive (mind-altering) substance, such as narcotics, alcohol, or nicotine. Physical dependency on such chemicals as prescription drugs or alcohol stems from repetitive use followed by the gradual increase in the body’s tolerance to, or ability to assimilate, that drug. Thus, increasingly larger doses must be consumed to maintain the...